The isup-oli SIP URI Parameter

A SIP URI parameter "isup-oli" is being used for interworking the ISUP Originating Line Information parameter or equivalent PSTN signaling information with SIP. This parameter has been also been discussed in various documentation, but nowhere is it formally documented. This document formally documents the usage, syntax, and semantics of this parameter, providing a reference for discussion of this parameter. It does not seek to achieve standardization of this parameter.